SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '693d15a1eafb2df606baba6bdab89447f6fd51b3551c2addb465ae654d31cbf8' 
  AND token = 'OV5wd9yoD/sMMbji30E5K4p+ZRwJhPycJ5no3wZwvRA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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