SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc13254d554740b1c31c269b851ff8cfbf73da53d249c1061310777e81710c8b' 
  AND token = 'tWHVANVdtkdumVDXkVFiblAyZLdAQpZwsggm9b2UCvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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