SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a7748a49d6076a5223b94dd0059c696277ba00c0b51f264301f68ab17e78ba9' 
  AND token = 'RHhXWKlgxKhKQlK8BlNyCcT6GL+OUoZTF8r8m5FlDRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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