SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e09a1ffdf38fb5e580c83796e3f847a7eb33ba80dfe2fba4bba01fb795ab95d' 
  AND token = 'o5OFumBVXvaEghY0s5GzkjFHlEVTRcCzcO0DMANx5GA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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