SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8c77b54fd75b5c38d74d0a1620090674c4a6707ea4952f027cb42af66647a59' 
  AND token = 'chqvl02ZwpFNN1Y5bLkqzR7/FDFLUppDpfkdse2aH/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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