SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb7c9fe653f50bdbf9568a2857f1bd9b024fdbbf9e63dad00fb959fad0a82dfe' 
  AND token = 'iw1ki0dgNHuwlX2d4o+5z+2LaUEYC7RCX1bd8TGPjFI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}