SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f38c4d1f2a02c1d9b7c1df0076340b02f00265b4a02f5033fc0d94c3e9a27d31' 
  AND token = 'EkTbqlG9vmu3GJKGH5r2YPmiVv4KysWwxrZBqoP+Jd4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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