SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd5caa0d442e75b8dd9ae704dba096a9792d3cb8881e8f4d6d7af842ef5848ec1' 
  AND token = 'PYmuEHSCfOjzq2qH/atvE6kB9audLWqZ4pgmSYqAguo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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