SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b2147a2ae42a6c6421b313d9b4fde53105b70db98fe5a008a524896bed1a039b' 
  AND token = 'JaYdZPGPMH3hlpOeAmzn3XVkDb0ybOCE9/6TA/vX1Sw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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