SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd178f04abcf479686aa3f14fbb8121a0f1704249972639a1bbc6ae14c6ec91ba' 
  AND token = 'FU5VMIs+lyK5PI8GxHUngK7ygvMlM2GMY5MRhCBroIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00358

JSON explain

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