SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0eaa0cd504410671e3e5a19e420501fa8a1d85dc246a8b70df0cca690b1b84ae' 
  AND token = 'Pf2hZ6n4+dEgmXdjShO56sXOINLA/IejKqO8VAMx25k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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