SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f57acd96d72f61609b4529ddc005e8ecf96c7007227f5fa72b42c2ec80c2a93' 
  AND token = 'iJ3wpVK46/J9ILISK+FiJnLdEyNaKyObZxyq4zFq3So=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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