SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b9fc2f3f9e50ad34e041dd972230f41fbc3c91814eecc8330c313b8bb677515d' 
  AND token = 'qamapR6JyVrRJlAyoafxkenYsq2CJXpNyelQuP9kTLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}