SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cea5763df23896aeb6ee545026a2837675d0928539697d4538823cefe014196e' 
  AND token = 'Wd8DROQ3qTVEqKT2EGbMBXUx5ruaLbY0uVd4EAXvMcI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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