SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1928c351ef87852cafbebbadaee25ff481de9ec46479d1daa758b908e12af46' 
  AND token = 'UqdP8oMEXPKDByTkjTsg17d8v/dTT3sJJgNHVf66wCs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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