SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1289f525b372ffc56c0197faddc7d082815e88be2835a5e815f157559675d4b3' 
  AND token = 'Wt4k7pVioh2io9cVneZjU+nW2OAz9hAYGKJT6OqwPFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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