SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05491b263a7fc3fadff05a47d21d22601fe230a89b80285e1acdc08bc4151d0c' 
  AND token = 'jmbkhXJWjhEVgUHXFvT/VTls1GZEtC5UoRWPFHVb8v8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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