SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97f8d28ede1b538aa0047986989006592213e826f75d0323f58e43894b8a618e' 
  AND token = '7NIkfGsZKaca3HDsJXUAgP9XRcztlkZOQqTH6B8PhPE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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