SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e49524388bfce81ec00d628d10e26c3543d1d64c145fbdbb53e6fc52b20bc4f5' 
  AND token = 'LJSD6FBfjD1DvRzkO/fE3bYAQeISResgBEx6jz5XfR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}