SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fae6cb54b142a836e9a106c975fe1a19797cce84e20676da0da7691ff1d1fbba' 
  AND token = '13kuL2GSQ9fgUJziAJ1cSNdMYcXjnurCkzUn7+gTQRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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