SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '39f36bc86f759007ea31754db129df3065b3c0a07d6c61c4c98272642553058f' 
  AND token = 'yRfYD21M52jAq17u9/GHIX5/GZ7LPAdR3EFBdoplPng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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