SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc4ee00efb5cf61083785902edf592a2f1afbca68551685211203f0736e1fad6' 
  AND token = 'zeSDPwSIwE5TLFCFAr8DN9v+MOx14vlnoEJ7kBDAqc4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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