SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41c785c4259ee97c49c5242dcc6990813efc7524acb2266dfe4bacfd43562c9d' 
  AND token = 'yRPlg3JiMb5Iq+PGINWW491ySN/+N1bqVUbXdWwm2XY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}