SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a563f8851a7faaba074669a4fcc8a1332ecc17932cc61a5085a5965cfc022e61' 
  AND token = 'AywaApOvIP9XtmrvfeOqETTDhRZyjTaZ7AXPbGVa9xM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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