SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '26a6172f8f5afad71d34c5d96cc8051b7348430f0f20e7f713adbf8590621c07' 
  AND token = 'SqCVchvGncy7E0WI+giQtXqLRvAoxe8xemA4j/Tn2M0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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