SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afb81ec10bad07de336e7db58b6c7985dfbff064c709042b0b6eb9ab2fa1baf2' 
  AND token = 'aw/dQ+HwX2Usy6rdikHI96D+XB6LMdDNb26Z30KlMRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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