SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fcdc032dcbccc8a28215b812c8e2ca0b0b656fc58b77397cc8f164ac7620b89e' 
  AND token = 'sqkr06s3Z3GOMwWsMWB1biMMQMc+UPbZgHC5BvBiDeI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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