SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5dc01b39f4a89529261c042f9b9b389b8ddef4d36fb85eb847132810504dd2a0' 
  AND token = 'BRYPh/wBj8nA7F9/O4MUz1JRGyGLkysOkhUssrOTZo8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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