SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c71754fdfc82ebc59d8ef86321e4a8d893c5c33cf5f70b412faea18d6b95e232' 
  AND token = 'FTrSc8YCMT25We3mCpjUbGFcsQp6Tk1VVnxwYO00vIc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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