SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c3a72244793afb779ba462895e8838d62ae285fd1b82e55fcd77854f91811938' 
  AND token = 'F+0pnwVgq9eIrg1RAxYzTTNPg4HbgwWlRO5KRLVgNk4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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