SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b87b12027e7a1e9575eb6233458c7f57dc28bcb1a26c6ff0d4756f264bded95d' 
  AND token = 'XCrrFNRWnHe8vOnGpwuF/FCS6UjTvMRa8iojqfHMBVA=' 
  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"
    }
  }
}