SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2edde88cef3c216fdced937c33513694e077206ddd5221e32e84ff2425af2bc8' 
  AND token = 'ilyRy9diNLPGDwf2KL05U6JzZouOpW/7dxfWNZR8/h4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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