SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f31917819657bf50bdbe024b52e8484dcce42a7e8a15ea466d36ef1615f59c22' 
  AND token = 'cLBHF3wDWThGUoCM1q+2fxDCia7X6Jh1hpnC2J7K/6I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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