SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4aad32b47442923bdc0fed72c70e64367761fe789f18da2b57e16bccd88fca56' 
  AND token = 'bG8VBukD7Ar88Qe/9lnZon/TOBMLikCSRZhr0QS/n1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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