SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07fd83e36495f2e9eaeea97af01756f2fdf540ef6214b2d0f99327341cb1921f' 
  AND token = 'CcfArf7sa8nXQHXQVlu7LgJ3+OSIe4TsJr1n4OdfQQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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