SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2aac2ecd8b377ae5683e6031a0915eea13e195f6d54fed33688a342a8745146' 
  AND token = 'qNRAlg1YjfhA2INxjDpGMr9I1WNaRHolurZpy7LHxmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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