SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73433d1815c0ccf8eb8f6715f455cfaacbcf77e0c12ee671663d682c17ca853a' 
  AND token = 'LqJzdncmcGdqGxafKAMaD+x2YbLgvy1pGSVnT+xS89k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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