SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9d697214da128a33e250a06286cab0761a86cbdc59eed4002451530e56484c9' 
  AND token = 'rfinWD5Hl9gv+PoSFdou9M4k/Lka/AA4DMhmQgyUetM=' 
  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"
    }
  }
}