SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e11efad17c8adf0d3dd0270b96165df4eb128761e584ddf3f039ef7bf88f27a3' 
  AND token = 'Kmyv0CKyh8Uv/z7GLBZ912s4ATcRrwZGlCMSJU+p7W8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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