SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '096363591757f22bd03ba7f989aa83b0b2e76c01dfc224296bd8256772909bb3' 
  AND token = 'ea49P8KMny8/9PkW2ReVem9sGT0w0UGSHJuei2J20H0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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