SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ea4c7e37b37304653374a87fc69571b2dc230c44acfe588234f7af9fd3041a3' 
  AND token = 'Qy8qvtR6emN3uW0LEiT3/VphpRdFeiSLW2UYCrHT6Lk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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