SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e569b9a8c31d9475c6b552aa3726dd56e69fe5b2f79f226a0f936b48eb9e58d7' 
  AND token = '4m/+Xga3lOiGkx/UzgoEx674FQfApwWzW/3hXV2yZTU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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