SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3af359166aabd2caeb7bf1e53ab5908bcdd8186be5475058021409c56731639d' 
  AND token = 'E4X+pCUtxoWjHeBDOX9q52sF4cGHzZXvmvsLYY8tA5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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