SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7cbf690e432b9dd4445713761e347c3829f0582aac123db556cb8420cfc181a9' 
  AND token = 'JwW0xTio7j7HGkqHVVnR7QSk48em/PolBMn+V6gjG0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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