SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dce86f755f5b3cea1f8e2385ab673898d38793d9d9ccad5702cc2355ae7e06d2' 
  AND token = 'zo9Wu1wnjoIZdb85rzoFzOZo3mPJMcrxye3GQefWMLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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